List two essential roles of the ribosome during translation.
List two essential roles of the ribosome during translation.
Solution and Explanation
Two essential roles of the ribosome during translation are as given below:
(a) Ribosome acts as the site where protein synthesis take place from individual amino acids. It is made up of two subunits.
The smaller subunit comes in contact with mRNA and forms a protein synthesizing complex whereas the larger subunit acts as an amino acid binding site.
(b) Ribosome acts as a catalyst for forming peptide bond. For example 23s r-RNA in bacteria acts as a ribozyme.
Top Questions on Molecular Basis of Inheritance
- The RNA triplet UAG acts as a stop codon which terminates the synthesis of a polypeptide. Below is given a strand of DNA which codes for four amino acids.
In which position will an insertion of a thymine nucleotide result in the termination of translation?
DNA strand:
3′ T C C A C C C G A T G C 5′- CBSE CLASS XII - 2025
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Concepts Used:
Translation
The translation is the process of converting nucleic acid information into amino acids. It also relates to the process of producing proteins from mRNA templates.
Components of Translation:
The main components of translation include :
- mRNA of both Eukaryotes and Prokaryotes
- tRNA - It helps in sending commands or transferring the information between protein and nucleic acids.
- Ribosomes - It contains ribosomal RNA and proteins, therefore, it is called the manufacturing unit of a cell.
- Enzymes - It is required for the formation of a peptide bond between the amino acids and also to attach amino acids to the accurate tRNA molecules.
- Proteins - They are the soluble factors, which are required for proper initiation, elongation and termination of translation.
Translation Process:
The three stages of translation are-
- Initiation involves assembling ribosomes around mRNA and activating amino acid and delivering it to the transfer RNA.
- Elongation is the process in which the RNA strand gets longer by adding amino acids.
- The termination process only involves releasing a polypeptide chain.